1. Process for the production of fuel additives in which in a first step isobutanol is subjected to a simultaneous dehydration and skeletal isomerisation to make substantially corresponding olefins, having the same number of carbons and consisting essentially of a mixture of n-butenes and iso-butene and in a second step the butene mixture is subjected to etherification, said process comprising:
a) introducing in at least one reactor a stream (A) comprising at least 40 wt % isobutanol, optionally an inert component,
b) contacting said stream with at least one catalyst in said reactor(s) at conditions effective to simultaneously dehydrate and skeletal isomerise at least a portion of the isobutanol to make a mixture of n-butenes and iso-butene,
c) removing the inert component if any, recovering from said reactor(s) a stream (B) comprising a mixture of n-butenes and iso-butene,
d) sending the stream (B) to at least one etherification reactor and contacting stream (B) with at least one catalyst in said etherification reactor(s), in the presence of ethanol andor methanol, at conditions effective to produce ETBE andor MTBE respectively,
e) recovering from said etherification reactor a stream (E) comprising essentially ETBE andor MTBE, unreacted butenes, heavies, optionally unreacted ethanol andor methanol respectively,
f) fractionating stream (E) to recover ETBE andor MTBE.
2. Process according to claim 1, wherein the stream (A) comprises at least 70 wt % of isobutanol.
3. Process according to claim 1, wherein the stream (A) comprises one or more C4 alcohols other than isobutanol.
4. Process according to claim 1, wherein the stream (A) used in step a), andor methanol andor ethanol used in step d) are issued from renewable energy sources.
5. Process according to claim 1, wherein the stream (A) is subjected to a purification treatment before step b).
6. Process according to claim 1, wherein the WHSV of the isobutanol is at least 1 h\u22121.
7. Process according to claim 1, wherein the temperature of the simultaneous dehydration and skeletal isomerisation of isobutanol ranges from 200\xb0 C. to 600\xb0 C.
8. Process according to claim 1, wherein the temperature of the simultaneous dehydration and skeletal isomerisation of isobutanol ranges from 250\xb0 C. to 500\xb0 C.
9. Process according to claim 1, wherein the temperature of the simultaneous dehydration and skeletal isomerisation of isobutanol ranges from 300\xb0 C. to 450\xb0 C.
10. Process according to claim 1, wherein the catalyst for the simultaneous dehydration and skeletal isomerisation is a crystalline silicate of the group FER, MWW, EUO, MFS, ZSM-48, MTT, MFI, MEL or TON having SiAl higher than 10,
or a dealuminated crystalline silicate of the group FER, MWW, EUO, MFS, ZSM-48, MTT, MFI, MEL or TON having SiAl higher than 10,
or a phosphorus modified crystalline silicate of the group FER, MWW, EUO, MFS, ZSM-48, MTT, MFI, MEL or TON having SiAl higher than 10,
or a silicoaluminaphosphate molecular sieve of the group AEL,
or a silicated, zirconated or titanated or fluorinated alumina.
11. Process according to claim 1, wherein the pressure of the reactor(s) of the simultaneous dehydration and skeletal isomerisation of isobutanol ranges from 0.5 to 10 bars absolute.
12. Process according to claim 1, wherein stream (E) recovered from step e) is fractionated to recover unreacted butenes andor unreacted ethanol andor methanol.
13. Process according to claim 12, wherein at least a part of said recovered unreacted butenes andor at least a part of said recovered unreacted ethanol andor methanol are recycled to the etherification reactor(s).
14. Process according to claim 12, wherein at least a part of said recovered unreacted butenes are sent to a purification zone before being sent to at least one oligomerization reactor andor to at least one alkylation reactor to produce heavies.
15. Process according to claim 14, wherein said unreacted butenes are subjected to a purification step before being sent to oligomerization reactor(s) andor alkylation reactor(s).
16. Process according to claim 2, wherein the stream (A) comprises at least 80 wt % of isobutanol.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A protector for a capping facility in the form of a capping mechanism for a pagewidth printhead having a plurality of nozzles located along the printhead, and wherein:
a) the capping mechanism comprises:
i) a capping member which has a length corresponding substantially to that of the printhead and which is configured to contact the printhead in nozzle capping engagement,
ii) a carrier supporting the capping member, and
iii) an actuating mechanism arranged to effect movement of the carrier back and forth between a first position at which the capping member is located remotely with respect to the printhead and a second position at which the capping member is located in contact with the printhead;
b) the capping member is pivotally mounted to the carrier and is arranged to pivot relative to the carrier during back and forth transitional movement of the carrier between a transition position and the second position, where the transition position is located intermediate the first and second positions; and
c) the protector comprises a covering member which is arranged to be engaged by the capping member when the capping member is located in the first position.
2. The protector as claimed in claim 1 wherein the covering member is constituted by the carrier.
3. The protector as claimed in claim 2 wherein the actuating mechanism is arranged to move the carrier pivotally between the first and second positions during a capping operation.
4. The protector as claimed in claim 2 wherein the carrier is pivotally mounted to a support by way of a pivotal element having a first pivot axis, and the capping member is pivotally mounted to the carrier by way of a pivoting arrangement having a second pivot axis that is located parallel to and spaced from the first pivot axis.
5. The protector as claimed in claim 4 wherein the capping member has a capping element that is radially displaced from the second pivot axis, and the radial displacement of the capping element from the second pivot axis is small relative to the spacing between the first and second pivot axes.
6. The protector as claimed in claim 5 wherein the spacing between the first and second pivot axes is of the order of three times the radial displacement of the capping element from the second pivot axis.
7. The protector as claimed in claim 5 wherein the capping element comprises a substantially rigid channel-shaped element.
8. The protector as claimed in claim 5 wherein the capping element incorporates a lip which is formed from an elastomeric material.
9. The protector as claimed in claim 8 wherein the capping element is arranged to engage with a face portion of the carrier when the carrier is located in the first position whereby a recessed portion of the capping element is effectively closed against loss of contained moisture and ingress of contaminating material.
10. The protector as claimed in claim 5 wherein the capping element incorporates a lip which is formed from an elastomeric material, wherein the lip is configured to locate about the printhead nozzles when the capping member is in the second position, and wherein the lip is arranged to engage with a face portion of the carrier when the carrier is located in the first position whereby a recessed portion of the capping element is effectively closed against loss of contained moisture and ingress of contaminating material.
11. The protector as claimed in claim 2 wherein the transition position is located a distance from the second position which is small relative to the distance between the first and second positions.
12. The protector as claimed in claim 11 wherein a ratio of the transitional pivotal movement of the carrier to a total pivotal movement of the carrier between the first and second positions is within the range 1:12 to 1:20.
13. The protector as claimed in claim 2 wherein the capping member is provided with at least one first stop member that is arranged to contact the printhead and thereby to effect pivoting of the capping member relative to the carrier as the carrier makes the transitional movement from the transition position to the second position.
14. The protector as claimed in claim 2 wherein the capping member is provided with at least one second stop member that is arranged to contact the carrier and thereby prevent pivoting of the capping member relative to the carrier as the carrier moves from the transition position to the first position.
15. The protector as claimed in claim 2 wherein the capping member is pivotally mounted to the carrier by a pivot shaft which extends along a marginal edge portion of the carrier.
16. The protector as claimed in claim 2 wherein a biasing device is mounted to the capping member and engages the carrier in a manner to bias the capping member in a direction away from nozzle capping engagement with the printhead.
17. The protector as claimed in claim 16 wherein the biasing device comprises a torsion spring.
18. The protector as claimed in claim 2 wherein the actuating mechanism comprises an electric motor which is coupled to the carrier and arranged to impart pivotal motion to the carrier by way of a crank and a motion translating mechanism.
19. The protector as claimed in claim 2 wherein at least one abutment is located adjacent the printhead and is operable to effect pivoting of the capping member when the carrier approaches the first position, whereby the capping member is moved away from a print media feed path.